Pressure-gage.



PATENTED JULY 5, 1904.

G. SPENCER.

PRESSURE GAGE. APPLIUATION FILED NOV.10, 1903.

H0 MODEL.

Wibaesses: 17 M c. m zmw 1 UNITED STATES Patented July 5, 1904.

PATENT OFFICE.

GEORGE SPENCER, OF SOMERVILLE, MASSACHUSETTS, ASSIGNOR TO CROSBY STEAM GAGE & VALVE CO., OF BOSTON, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS.

PRESSURE-GAGE.

SPECIFICATION forming part of Letters Patent No. 764,016, dated July 5, 1904. Application filed November 10, 1903. Serial IIo. 180.594. (No model.)

To all whom, it may concern.-

Be it known that I, GEORGE SPENCER, of Somerville, in the county of Middlesex and State of Massachusetts, have invented certain new and useful Improvements in Pressure- Gages, of which the following is a specification.

My invention relates to a certain improvement in pressure-gages, and more particularly to the dial and index-hand employed to show the pressure; and its object is to enable one using the gage and desiring to maintain a constant pressure (a. e., two hundred pounds) to readily and quickly find on the dial the number indicating such pressure. To accomplish this object, I repeat that particular number and place it in a conspicuous place by itself on the dial and provide an additional indexhand which points to such number whenever and as long as the desired pressure is maintained.

My invention is especially adapted for use on locomotives, where a fixed pressure of steam is usually required, as it enables the engineer to see at a glance whether the required pressure is being maintained.

The invention is illustrated by the accompanying drawings, in which Figure 1 is the front view of a gage embodying my improvement. Fig. 2 is aview of the additional dial. Fig. 3 is aview of the central section of the small index-hand and its mounting. Fig. 4 is a similar view of the large index-hand. Fig. 5 shows an interiorlythreaded conical wedge. Fig. 6 is an ordinary screw.

Similar letters refer to similar parts in the several drawings.

A is the usual dial of a pressure-gage marked or calibrated to show pressures from naught to three hundred pounds. It is fastened to the gage-socket by the screws a a. Through the central opening a of this dial extends the upper end of a pinion employed to transmit the action of the gage mechanism to the index-hand H, and over this upper end of the pinion fits in frictional contact the cylindrical sleeve It, having at its upper end the shoulder 72., to the under side of which is fastened the index-hand H. A second sleeve k, similar to sleeve it, has a slitted lower portion and a conical interior, so that it may be distended to fit tightly in the sleeve h, and has fastened to the under side of its shoulder 70 the additional index-hand K. To distend the sleeve is, I employ the interiorly-threaded tubular conical wedge W, whose smaller end easily enters the sleeve h from below. The screw w is adapted to enter the sleeve la from above and engage the wedge W and draw it up into the sleeve, thus distending the lower portion of the sleeve is. The dial A hasa cut-out portion a near the top, and through this aperture can be seen the number 200, which is one of the series of numbers 160 to 220 appearing on the dial B. This dial B has a central opening 6, adapted to receive the screw 7/, by which it is rotatably fastened to the back of dial A. The dial B has placed around its outer circumference certain numbers between 160 and 220, and between these several numbers it has the holes 5 6 These numbers and holes are so placed in dial B that when a number (a. e., .200) is directly behind the opening a in dial A one of the holes in dial B will register with the screw 64, which locks the dials together and fastens them to the gage-socket, and two of the holes in dial B will appear in the opening a in dial A for the purpose hereinafter explained. The additional dial and index-hand are prepared for use or are set as follows: Assuming that the desired pressure is two hundred, we first remove the screw a', which locks the dial B in place and prevents its rotation, and rotate dial B till the number 200 appears through the openinga in dial A. The rotating of dial B is done by means of any pointedinstrnment inserted in the perforations b 6 Then the screw a is replaced, thus locking the dials together. The additional index-hand K is mounted on the index-hand H at such angle that when the index-hand H points to the number 200 on dial A the additional index-hand K will point to the number 200 appearing in the opening a Before the index-hands are fastened together at the desired angle the index-hand H is mounted on the above-mentioned pinion in the usual manner. By placing upon the smaller dial B a series of numbers,(a. e. 160 to 220,) locating them in the same circle with the number 200, so that by rotating dial B the numbers appear successively in the opening (0 I make the invention applicable in any case where a pressure between one hundred and sixty to two hundred and twenty pounds is sought to be maintained. A number of additional dials covering the whole range of pressures may be used with the same gage in the way I have described, and any additional dial may be marked as desired. This adjustability of the additional dial and of the additional index-hand is the feature of my invention.

What I claim as my invention, and desire to secure by Letters Patent, is

1. In a pressure-gage the combination, with the arbor and dial mechanism, said mechanism having thereon the usual numbered pressurescale and in addition thereto a number con spicuously arranged thereon in a fixed standard position and designating the normal pressure at which the gage is intended to be used, of two indicating-hands mounted upon the arbor at such an angle to one another that when one points to said normal pressure on the ordinary scale the other points to said' superaddecl number; substantially as described.

2. In apressure-gage the combination, with the arbor and dial mechanism, said mechanism having thereon the usual numbered pressurescale and in addition thereto a mark conspicuously placed thereon, of two index-hands, one index-hand being adjustably fixed to the other index-hand, with means for holding the adjustment; substantially as described.

3. In a pressure-gage the combination, with the arbor and dial mechanism, said mechanism having thereon the usual numbered pressurescale and in addition thereto a mark conspicuously placed thereon, of the index-hand H and the index-hand K fixed adjustably together and held in adjustment by the wedge W and screw w, together with said wedge WV and said screw w, the former being conical and interiorly threaded for engagement with the latter; substantially as and for the purposes set forth.

4. In a pressure-gage the combination, with the arbor and dial mechanism, said mechanism having thereon the usual numbered pressurescale and in addition thereto a mark conspicuously placed thereon, of the index-hand H, sleeve h, index-hand K and sleeve 71:, fixed adjustably together and held in adjustment by the wedge W and screw w; substantially as and for the purposes set forth.

5. In a pressure-gage the combination of the dials A and B, the index-hands H and K, the screw 6, the screws a and a, the sleeves it and 7c, the wedge IV and the screw w; substantially as described.

In testimony whereof I have affixed my signature in presence of two witnesses.

GEORGE SPENCER.

Witnesses:

SARA A. HERRICK, RALPH W. FOSTER. 

